Working Papers

Using the "firm" quotes obtained from the tick-by-tick EBS (electronic broking system that is a major trading platform for foreign exchanges) data, it is found that risk-free arbitrage opportunities--free lunch--do occur in the foreign exchange markets, but it typically last only a few seconds. "Free lunch" is in the form of (a) negative spreads in a currency pair and (b) triangular arbitrage relationship involving three currency pairs. The latter occur much more often than the former. Such arbitrage opportunities tend to occur when the markets are active and volatile. Over the 12-year, tick-data samples, the number of free lunch opportunities has dramatically declined and the probability of the opportunities disappearing within one second has steadily increased. The size of expected profi...

Using tick-by-tick data of the dollar-yen and euro-dollar exchange rates recorded in the actual transaction platform, a "run" -- continuous increases or decreases in deal prices for the past several ticks -- does have some predictable information on the direction of the next price movement. Deal price movements, that are consistent with order flows, tend to continue a run once it started i.e., conditional probability of deal prices tend to move in the same direction as the last several times in a row is higher than 0.5. However, quote prices do not show such tendency of a run. Hence, a random walk hypothesis is refuted in a simple test of a run using the tick by tick data. In addition, a longer continuous increase of the price tends to be followed by larger reversal. The findings suggest t...